The Mentored Clinical Scientist Development Award (K08) will allow the candidate to develop into an independent researcher who will conduct both basic and translational research in the field of neonatal medicine. Over the course of this award, Dr. Maltepe will embark upon a didactic and research program designed to provide him with additional training in proteomics and mass spectrometry techniques. He will utilize his mentor's expertise in this area to further explore the epigenetic mechanisms enabling the Hypoxia- Inducible Factor (HIF) family of proteins to regulate hypoxia responses and determine stem cell fate. The specific aims are as follows. (Aim 1) Analyze alterations of well-defined histone modifications in response to hypoxic culture in wild-type and HIF-null mouse embryonic fibroblasts as well as during differentiation in wildtype and HIF-null trophoblast stem cells. (Aim 2) Determine the nature of HIF-interacting chromatin remodeling complexes under the above conditions by utilizing immunoprecipitation, candidate protein immunodetection, and mass spectrometry techniques. (Aim 3) Interrogate the chromatin-associated subproteome for global alterations of histone post-translational modifications under the above conditions using quantitative proteomic and mass spectrometric investigation. (Aim 4) Analyze genome-wide changes in the methylation status of CpG islands under the above conditions using arrays of BAG clones and the methylation-sensitive restriction enzyme Notl. The information obtained from these studies will form a sound foundation to further study the mechanisms responsible for integrating physiological and epigenetic inputs. The developed methodologies will serve as translational tools to study perinatal stressors associated with preterm birth and the intra-uterine programming of adult disease. By carrying out this research plan the candidate will receive all the necessary training to become an independent investigator pursuing an academic research and teaching career in neonatology. As for relevance to public health, a great deal of evidence now suggests that the environment in which a baby develops before birth is an important factor in programming adult health. For example, babies that are stressed in the womb have an increased risk of developing cardiovascular disease and type II diabetes. This proposal seeks to explain these enigmatic associations in term of the molecular causes. (End of Abstract)